Multiple pregnancy Flashcards
Incidence of twin pregnancy/ 1000
Far east
Europe
Nigeria
Far East
- 2-7
Europe
- 9-20
Nigeria
- 20-45
Reason for rising incidence of multiple births
IVF
- Insertion of multiple embryo
Ovarian hyperstimulation
Use of clomifene to increase fertility
Zygosity
Number of eggs fertilised
1= monozygotic= identical
- 1/3 are dichorionic
2= dizygotic= non-identical
Chorionicity
Description of the number chorion sac and the placenta.
- Early spiltting= dichorionic
Monochorion
- One chorion
- One placenta
- Vascularly joined placenta
- Increased loss rate [3x]
Dichorion
- Separate chorion
- Separate placenta.
- All dizygotic twins are dichorionic
Amnioticity
Describes the number of amniotic sacs in multiple pregnancy.
Monoamniotic (MA)
- One amniotic sac shared
- Only with monozygotic twins
Diamniotic (DA)
- Separate amniotic sac
MCDA
Monodichorionic, diamniotic twins
- Common chorion
- Joined placentae
- Separate aminion
Can only occur with monozygotic twins.
Splitting occurs in early blastocyst phase
- Forms 2 inner cell masses
MCDA
Monodichorionic, diamniotic twins
Can only occur with monozygotic twins.
Splitting occurs in early blastocyst phase
- Forms 2 inner cell masses
MCMA
Monochorionic, monoamniotic twins
- Common chorion
- Common amnion
- Shared placenta
Only occur with monozygotic twins
- Occurs when splitting occurs in later blastocyst when there is one inner cells mass
Greater complications
- I.e TTTS
Diagnosing multiple twins
Ultrasound
- Uterine size
- Lambda sign= chorionicity
Half of multiple pregnancies are diagnosed during deliver - worldwide.
Risk of multiple pregnancies to mother
Intensified symptoms of pregnancy
- Hyperemesis
Anaemia
Hypertension/ pre-clampsia
Delivery problems
Risk of multiple pregnancies to fetus
Intrauterine growth restriction
Pre-term labour
Perinatal mortality
First trimester management of multiple pregnancy
Chromosomal anomalies screening
Determining chorionicity
If 3 or more
- Consider fetal reduction
Second trimester management of multiple pregnancy
Detect fetal abnormality
Scans for growth
- DC monthly, from 24 weeks
- TTTS in MC twins, 2 weekly 16-28, then monthly
Assessment of maternal complications
Twin to twin transfusion syndrome
- Mechanism
- Complications
- Treatment
Unbalanced placental vascular anastomoses
- Blood is shunted from donor baby to recipient baby
- Monochorionic twins
Donor baby
- Growth restricted
- Less amniotic fluid
Recipient baby
- Fluid overload
- Heart failure
- Fluid pools
High mortality rate
Rx
- Laser treatment
- Amnio-reduction
Third trimester management of multiple pregnancies.
Monitor blood pressure.
Delivery planning
- 37-38 for DC twins
- 36-37 for MC
Vaginal or caesarian?
